Thomas David Nicholls (September 16, 1870 – January 19, 1931) was an Independent Democratic member of the U.S. House of Representatives from Pennsylvania. Thomas D. Nicholls was born in Wilkes-Barre, Pennsylvania. He moved to Nanticoke, Pennsylvania, with his parents. He worked in mines as a boy. He studied mining by correspondence and passed a state examination in 1897, received a mine foreman's certificate of competency, and was appointed superintendent of mines. He was district president of District No. 1 of the United Mine Workers of America, from 1899 to 1909, resigning on account of ill health.